Compressible floor tile



March 13, 1956 E. S. ROBBlNS COMPRESSIBLE FLOOR TILE Filed Aug. 21, 1952 E. Siam lg Bobbins United States Patent.

COMPRESSIBLE FLOOR TILE Edward Stanley Robbins, bins Floor Products, tion of Alabama Killen, Ala., assignor to Rob- Inc., Tuscumbia, Ala., a corpora- This invention relates to an improved type of floor tile and to methods of using the tile.

Both floor tile and linoleum are in common use today in home flooring and in commercial flooring. The ease of designing decorative patterns has given considerable impetus to the use of floor tiles, since the tiles when laid may be selected and placed so as to conform to any design chosen. This adaptability to any decorative scheme, plus the relatively low cost of tile, has led to increased use of tiles in finishing basements in homes, in such commercial establishments as barber shops, and in fashionable stores. This widespread use of floor tiles has brought to the attention of the public and to the attention of those skilled in the art several of the present disadvantages of using tile. terial, tends to wear through in the well-travelled areas before other areas show any wear at all. At present, the cost of repairing the floor is very high, since a large section of tile must be removed, then the adhesive must be completely removed, the subfioor surfaces must be freshened, new adhesive must be applied, and finally, fresh tile may be laid. In order to do this properly, a larger section of tile must be removed than is to be replaced. The presence of the adhesives is often undesirable, since, in general, the adhesives have objectionable odors, are sticky, and black, and, thus, tend to stain adjacent tile. Their use in hospitals, for instance, is not relished. There is also a necessary time interval for allowing the adhesive to set. And, unless all the old tile is removed, a patchwork job results, since the old tile is always faded and scuffed.

In addition to the serious disadvantages mentioned above, the use of tile in damp basements or other damp areas is not practical because the adhesive fails after any substantial contact with moisture. If rubber tile is used, not only will the adhesive fail, but the tile will absorb water and curl or buckle. The use of the commonly available rubberor plastic tile or linoleum has the disadvantage that floor coverings made therefrom lack resiliency. The tile or sheet linoleum is usually made flat on all surfaces. The top is flat to provide a good walking surface. The bottom is flat, or perhaps matted, to provide a maximum area of contact with the adhesive. There is very little cushioning effect between the load and the subfloor, since all shocks are transmitted directly to the subfloor. The adherence of all of the tiles tends to prevent lateral movement of the subfioor, and adds to the non-resilient eifect. The tile in efiFect acts as little more than a protective covering over the subflooring. This lack of resilience in rubber or composition tile is most noticeable when such tiles are supported upon a concrete slab subfloor. In such installation a sharp impact or blow on the surface of the tile will permanently dent or break the surface instead of being absorbed. 7

It has also been noticed that tile floors are considerably affected by seasonal changes in wooden subflooring. It is well known that in winter, warm hot .air from central For instance, tile, like any other flooring maheating units dries out wooden flooring. The flooring shrinks as it dries, and the joints open up. Any tilm fastened to the wooden flooring naturally tend to open up at the seams along with the wood. In the summer months, the heat and humidity causes expansion of the individual members of the wooden flooring. The tile attached moves with the flooring, and in many cases, buckling of the tile occurs.

With these and other considerations in mind, a new type of compressible, resilient tile and a new method of installing such tiles have been developed. In developing the new type of tile, the object was to produce a tile which could be laid on all types of subflooring without the use .of adhesive.

A further object of the invention was to produce a tile flooring which would be more resilient than present floorings, capable of absorbing some of the shocks of floor loads itself, and also capable of allowing greater lateral movements of the subflooring than is now possible.

Another object of the invention was to produce a tile which could be used in damp basements and in any other damp area, such as laundries, kitchens, cafeterias, or on below-grade concrete surfaces without the tiles becoming dislodged in the event of exposure to water.

Along with these other desiderata, it was also an object of this invention to develop a new method of laying compressible resilient tile without the necessity of using adhesives.

These and other objects of the invention have been achieved by the use of a tile made of flexible polyvinyl chloride resins. The tile is made in conventional squares or blocks of any convenient size. The nine inch by nine inch square size is preferred. The squares are made of greater depth than is customary, depths of three-sixteenths of an inch to one-half inch being preferred for home use. The tile square or block is perfectly squared-off on all sides. The lower or bottom side is recessed or hollowed out, and within the hollow or recess are variously shaped projecting members, suchas, for instance, straight ribs, which depend from the lowermost face of the tile. The invention may be most easily understood by reference to the drawings.

In Fig. l is shown in perspective one embodiment of my improved tile, with the side which is normally positioned on the floor shown as the upper or visible side.

Fig. 2 shows this same tile in its normal position in contact with subfiooiing, in greatly enlarged cross-section.

Fig. 3 shows, in an enlarged cross-sectional view, two of the squares shown in Fig. 1 in abutting relation.

Fig. 4 is a plan view of a modified form of the tile square, showing the under surface of the tile.

Figs. 5 and 6 show in, a somewhat enlarged view, a side-elevational and a profile view respectively, of a side of one of the tile squares.

More specifically, Fig. 1 illustrates a tile square with reinforcing ribs 1. These ribs are of the same depth as the perimeter strip 2, so that the strip 2 and ribs 1 all are flush along the floor when the tile is in position for use, as shown in Fig. 2. To apply the tiles to a subfioor, two squares are placed with their side faces 3 and 3 abutting. Succeeding tiles are then laid until the floor is'coveredp No adhesive is necessary. The tiles are made preferably of a polyvinyl chloride plastic, so that a non-curling, non-absorbent, flexible tile is obtained. Similar plastics or rubber are equally useful. Any flexible moisture-resistant plastic composition will suflice. The tiles are retained in place by laying them under a slight compression which is an important feature of this invention. eighths of an inch in a length of keep the tiles in place.

18 feet is sufiicient to Concrete floor installation In order to make the use of my new tile more clear, a typical installation on a concrete floor will be described. The floor should be clean but need not be dry. A chalk line is drawn along a wall about the width of one tile square away from the wall. At a perfect right angle to the first line, another chalk line is struck along one adjoining wall, about the same distance out from the wall. The accuracy of the right angle can be quickly estimated by using the standard triangulation method measuring six feet from the corner on one line and eight feet on the other. he distance from each of these established points should be ten feet exactly. A course of tile is then laid along the lines around the two sides of the room, on the side of the chalk lines away from the walls. This course of tile is set in position by the use of a very small amount of any standard tile adhesive. The adhesive may be applied to the floor or to the tile. The adhesive is used only for this course, and the only purpose is to spot this course of tile in place, to assure a perfect right angle corner as a starting point for laying the rest of the floor. A quickdrying adhesive is preferably used, and while it is setting, the border tile can be laid along the two walls.

When the initial course of tile has been laid and is firmly secured in place, the remaining tiles are laid so as to cover the remaining floor space. The tiles are laid snugly against each other. Since no adhesive application is necessary, the operation can be very rapid. Before the last course of tile is laid, a wooden strip is placed against the edge of the tile then on the fioor, and a slight compression is applied to each course of tile, one course at a time. While each course is thus compressed, the final course of tile is easily slipped in place, one square at a time. in a course length of 18 feet, a final compression of about one-quarter of an inch is highly satisfactory. This corresponds to a compression of about 0.012" per tile, when the nine inch squares are used. The squares are trimmed to fit the space with a conventional trimmer, a knife, or with a tile cutter.

This slight compression adds to the natural spring of the tile. Shifting of the individual tiles under load is almost nil. Any expansion or contraction of the subfioor caused by temperature and humidity changes has no effect on the tile. It makes no difference if the adhesive bond on the first course of tile is later weakened or destroyed. The compression, alone, keeps all tiles in place.

It is obvious that if a room has two walls which form a perfect right angle with each other, no special first course need be spot-adhered to the floor. Instead, the first course may be laid directly along these squared walls, and no adhesive whatsoever need be used.

Wood floor installation This type of installation is similar to the concrete floor installation. As usual, the quarter round should be removed. The lloor should present a smooth surface. The chalk lines are drawn as before, but now the first course of tile is laid along the line and next to the wall. Small two-penny nails are used to secured this first course in place. The tile can be trimmed to fit as necessary with any ordinary tile cutter. The installation is completed by inserting the remaining tiles as necessary. No nailing is necessary where a perfect square is already available in the walls of the room.

The above examples are illustrative of the use of my new tile. The principal advantage is that it can be laid without the use of adhesive. In addition, the tile can be laid on and below grade on concrete, since dampness does not affect the installation.

The side edge faces 3, of each tile are perfectly squared off in relation to each other and to upper surface and lower surface 11. Thus, when the faces, 3 and 3, of two tiles meet in an installation under compression, as shown in Fig. 3, there is a perfect seal. The quality of the seal depends only on the trueness of the facing. In most cases the seal is sufficiently perfect to seal out all surface moisture. However, even where surface moisture is not sealed out, if some moisture trickles or seeps down to the subfioor, the water merely remains under the tile in the depressions in the under surface. There is no tendency, as would be the case with a solid tile, for water to squirt up through the joints when a load is applied to the tile floor.

In Fig. 4 there is shown a modification of the ribbed tile of Figs. 1, 2 and 3. Fig. 4 illustrates a Wattle-type back. The tile 18 has a regular pattern of square depressions 20, similar to those in a wafile. The perimeter ridge 19 surrounds all the depressions. Interior ridges 21 are of the same depth as perimeter ridge 19, so that the lowermost edges of the ridges 19 and 21 lie in the same horizontal plane and a cross-sectional view of Fig. 4 taken through the depressions 20 would present a substantially similar picture to that illustrated in Fig. 2. The uniform pattern of square depressions has the advantage over other patterns of ribs, diamonds, rectangles, circles, hollow circles, etc., which are possible modifications of my invention, in that the stresses of compression and the stresses of loads are absorbed by a tile which offers equal strength in all directions. Thus, when lateral forces of compression are applied to a tile having a uniform pattern of square depressions in the installation thereof, the tile is uniformly laterally compressed. This is a decidedly desirable feature in a floor tile, where uneven stresses tend to allow buckling of the tiles.

However, substantially any pattern of depressions on the rear face will provide the resiliency desired. In describing my invention, 1 have shown the ribbed structure of Fig. 1 and the preferred wafile or grid-like structure of Fig. 4. The essential elements, however, are the squared-off side faces, and the flexible, resilient, substantially uniformly laterally compressible body. While the pattern of squares on the rear face represents the preferred embodiment of the invention, a satisfactory tile may be produced which has but one depression adjacent the perimeter ridge 19, and which is coextensive therewith. Such a single depression can be of the same size and shape as depression 6 in Fig. 3. This depression could also be a series of smaller depressions around the tile periphery, such as a series of depressions 20 similar to those in Fig. 4, positioned one-deep only, just inside each perimeter ridge 19. This type of structure, with a depression adjacent to the perimeter ridge, provides the necessary cushioning effect which aids in providing and maintaining lateral compression.

Regardless of the particular type of under surface pattern which is used, added thickness, over and above the now conventional tile thickness, is desirable. This provides for added resiliency and life, and for deeper side faces 3 on the tile squares. The additional contact area provided by the deeper side faces 3 provides a more efficient seal between adjacent tiles, and also provides a greater area of frictional contact to aid in maintaining the tiles in place under compression. The added thickness also provides a stronger tile generally, and allows for greater final lateral compression without distortion of the top surface of the tile than would a thinner tile.

In Fig. 5 is shown a further illustration of the invention, showing in detail why a good seal can be obtained by my improved method of laying tile. When the side faces 3 are to be squared off, a stack of tile squares is placed in a large machine similar in action to a milling machine. In squaring off the faces, fine ridges 4 and depressions 5 are left on face 3. When the tile is laid, as shown in Fig. 3, these minute ridges are compressed. The compression gives a good sealing effect to the butt joint. The frictional contact also assists in holding the tiles in place.

The floor structure produced by these tiles has several advantages not mentioned above. The dead air space under the tiles in the depressions has considerable insulating value. There is also considerable sound absorption due to the cushion type structure. If one tile is damaged by gouging by a sharp pointed instrument, or if a group of tiles are seriously indented, as by a table, chair, washing machine, or other heavy object the tile or tiles may be individually replaced with little effort and slight expense. Similarly, a tenant may install his own tile floor; and, when he moves, he can take his floor with him. Test installations in barber shops and behind the counters of soda fountains have shown that this is a very easy type of floor to clean. The floor is not adversely affected by cleaning with ordinary cleansers and water. The floor is dust-tight as well as water-tight, and any spillage or accumulation of refuse comes up readily. In a test installation in a barber shop, it was found that hair tonic from a broken bottle could be cleaned up merely by mopping with a dry cloth. Previous experience with other forms of tile floors had been that wet mopping was necessary to pick up the tonic from crevices at the joints. Removal of all of the spilled tonic was absolutely necessary with other types of tile floor, of course, to prevent deterioration of the adhesive. The seal with my improved tiles is not only water tight, it is so tight that with a proper selection of patterns the joint between adjacent tiles is not visible to the ordinary observer, and the floor has a linoleum-like, continuous appearance.

Although I have illustrated and described my invention as applied to square tiles, it is obvious that any angular tile having a regular shape will be satisfactory. Any conventional material may be used for making the tile, although some materials are not as satisfactory as the polyvinyl chloride resin compositions. Materials which are satisfactory for making laterally compressible tiles are other synthetic resin compositions, linoleum-type compositions, rubber, synthetic rubber, and rubber-like compositions. Other materials will be obvious to those skilled in the art.

Iclaim:

1. A laterally compressible, resilient tile having substantially plane vertical sidewalls except for a plurality of minute ridges and depressions disposed on the surface of said sidewalls, and a flat perimeter portion around the bottom of said tile at right angles to the sidewalls bottom thereof at right thereof, said tile being adapted to remain in position under lateral compression when confined with a plurality of other similar juxtaposed tiles within an area smaller than the normal aggregate surface area of the tiles, said minute ridges and depressions providing frictional engagement between the sidewalls of abutting tiles.

2. A resilient, laterally compressible tile having a top, a bottom, and four sidewalls, said top being smooth and presenting a flat, unbroken plane surface, each sidewall being a substantially plane, vertical surface, forming a right angle with the top of the tile, each sidewall forming a right angle with the adjoining sidewall and with the bottom of the tile each side wall being substantially planar except for a plurality of minute ridges and depressions, said tile bottom presenting a continuous perimeter and a surface support area interior to said perimeter, the perimeter and support area comprising fiat portions of the tile in the same plane, said last-named plane being parallel to the plane of the top of the tile, said tile being adapted to be juxtaposed with a plurality of similar tiles under permanent lateral compression to form a surface covering the said ridges and depressions being adapted to make contact with the ridges and depressions in the side walls of abutting tiles in a frictional engagement hindering relative movement of the tiles.

3. A resilient tile floor comprising a group of juxtaposed flexible tiles under lateral compression, each tile being provided with vertical sidewalls which are substantially plane except for a series of minute ridges and depressions, and with a flat perimeter portion around the angles to the sidewalls, the minute ridges and depressions of abutting faces of adjoining tiles being embedded in each other by the compression, whereby a locked structure is formed which resists movements of the tile in a vertical direction.

References Cited in the file of this patent UNITED STATES PATENTS 1,054,423 Kennedy Feb. 25, 1913 1,927,882 Willnus Sept. 26, 1933 2,237,525 Peik Dec. 21, 1943 2,627,744 Lopina Feb. 10, 1953 2,632,536 Skeel Mar. 24, 1953 

